Refrigeration apparatus



y 4, 1961 F. P. CROTSER 2,990,698

REFRIGERATION APPARATUS Filed July 6, 1959 2 Sheets-Sheet 1 INVENTOR. FRANK P CROTSER ATTORNEYS July 4, 1961 F. P. CROTSER REFRIGERATION APPARATUS 2 Sheets-Sheet 2 Filed July 6, 1959 q M mu J INVENTOR. FRANK F? CROTSER ATTO NEYS United States Patent 9 M 2,990,698 REFRIGERATION APPARATUS Frank P. Crotser, Adrian, Mich., assignor to Revco, Inc., Deerfield, Mich., ascorporation of Michigan Filed July 6, '1959, Ser. No. 825,034

' 13 Claims. (Cl. 62-503) This invention relates to refrigeration systems such as are used in household refrigerators and home freezers. A refrigeration system of such type includes a compressor which pumps hot refrigerant in gaseous form into a con denser, in which the hot gas is compressed and cooled to a degree at which it emerges from the condenser usually in a liquid form. The refrigerant in liquid form passes from the condenser through a restricted passageway which usually is in the form of a narrow tube called a capillary tube. The capillary tube discharges the refrigerant into an evaporating coil where it vaporizes and absorbs heat of vaporization and from whence it is pumped by the compressor through a so-called suction pipe leading from the evaporator coil to the low pressure side of the compressor.

The system of coils, capillary tubing and piping is a closed system of substantially constant volume and is completely filled with refrigerant which is partly in the liquid phase and partly in the gaseous phase. The proportion of liquid refrigerant to gaseous refrigerant keeps changing and since the volumetric capacity of the system is small, fluctuations in pressure resulting from transformation of liquid into gas or gas into liquid are liable to be rather violent.

In order to reduce the extent and abruptness of fluctuations in pressure by adding volumetric capacity to the closed system and to provide a reservoir for temporary storage of such refrigerant as may emerge from the evaporator coil in droplets, a chamber, known in the refrigeration trade as an accumulator usually is interposed in the system between the evaporator and the suction pipe through which refrigerant gas is pumped back to the compressor. Accumulators often take the form of canisterlike cylindrical shells with one end connected to the evaporator and the other end connected to the suction pipe. In order that such liquid refrigerant as may be in the accumulator may not get into the suction pipe and be pumped into the compressor, the elongated shell which constitutes the accumulator is sometimes set upright or sloped with the end that is connected to the suction pipe uppermost. Therefore, accumulator shells that are upright or sloped do not fit into all refrigeration apparatus as neatly and compactly as would accumulator shells that are horizontal.

An object of this invention is to provide an accumulator shell and suctionpipe so constructed and connected that they function in a superior manner when the accumulator shell is positioned with its major axis extending horizontally.

Another object is to provide an accumulator shell and suction pipe combination in which surges of liquid within the accumulator shell are not liable to floodinto the suction pipe.

Another object is to provide a combination of capillary tube suction pipe and accumulator shell in compact heat exchange relationship, the accumulator shell lying with its major'axis' horizontal.

O'therobjects and numerous advantages of the invention will become yapparent upon perusal of the following description illustrated by the accompanying drawings in which: p z

FIG. I is a schematic plan view of a refrigeration system incorporating this invention; I

FIG. II is 'a plan view on an enlarged scale of the evaporator coil connected tolthe accumulator shell and Patented July 4, 1961 bination incorporating this invention;

FIG. III is an elevational view with parts in section showing the apparatus illustrated in FIG. II; and

FIG. IV is a fragmentary sectional View taken substantially as indicated by the line IV--IV of FIG. III.

These drawings and the description that follows illustrate and describe a preferred form of this invention but they are not intended to limit its scope.

The compressor 1 may be of any desired commercially available type. It is driven by a motor 2 and takes in refrigerant (which is a fluid having a low boiling point) in the gaseous phase at low pressure through an inlet 3 and discharges it at high pressure still in the gaseous phase through an outlet 4, from whence the refrigerant passes into a condenser 5 where it cools under pressure and liquefies.

The condenser 5 as Well as an evaporator 6 are shown schematically as made of piping but they may, of course, be made of sheet metal or may be of any desired construction.

Refrigerant in the liquid phase is conducted from the condenser 5 to the evaporator 6 by a capillary tube 7 which enters a suction pipe 8 at a fitting 9 and lies within the suction pipe 8. The capillary tube 7 lies within the suction pipe 8 along a sufficient portion of the lengths of the two tubes to transfer heat from the liquid refrigerant within the capillary tube to the gaseous refrigerant that is being pumped through the suction pipe thus cooling the liquid within the tube 7 and Warming the gas that is being returned to the compressorand thereby improving the efficiency of the system. The discharge end 10 of the capillary tube 7 extends into the intake end 11 of the evaporator coil 6 and the liquid fromv the capillary tube 7 is substantially completely evaporated into gas as it passes through the evaporator coil 6.

After passing through the evaporator coil 6 the refrigerant in the gaseous phase with such residual liquid as may remain therewith is led through a tailpipe 12 and a port 13 into the top of the accumulator shell 14. The suction pipe 8 with the capillary tube 7 therein enters the accumulator shell 14 through a nipple or coupling 15, which in the form shown in FIGS. II and III is swaged upon the open segment of one end of the accumulator shell, and extends entirely through the shell protruding from a similar nipple or coupling 16 swaged upon the other end of the shell. The portion of the suction pipe 8 that lim within the shell 14 thus extends from end to end in the upper portion or area of the shell.

Extending along the top of the portion of the suction pipe 8 that lies within the upper part of the shell 14 is a series of perforations through which gaseous refrigerant is drawn into the suction pipe 8. In accumulators of the prior art having ports into which suction pipes open, liquid refrigerant is liable to surge into the open ends of the suction pipes when agitation of the refrigerant occurs because of abrupt changes in pressure or for other reasons. ,With the suction pipe constructed and arranged in accordance with this invention, having no opening into the accumulator except the series of perforations 17 in its top which lie closely beneath the ceiling of the accumulator chamber, such surging of liquid refrigerant into the suction pipe cannot occur. Even with maximum agitation there is no liability that liquid may enter more than one or two perforations at once and there is little liability that liquid may enter the perforations at all.

Exteriorly of the nipple or coupling 16 the terminal section of the suction pipe 8 is crimped preferably at a plurality of places 18, around the capillary tube to form a substantially fluid-tight seal and the end of the suction pipe, which preferably is of aluminum, is soldered or otherwise connected with the fluid-tight joint to the inlet.

end of the evaporating coil 6, which preferably also is of aluminum, and into which the discharge end 10 f the capillary tube 7 projects. This construction eliminates any possibility of leakage of refrigerant into the air of the room. Any slight leakage of the refrigerant at the places 18 where the suction pipe is crimped around the capillary tube is of no significance since the refrigerant would leak only from the evaporator to the accumulator or vice versa, the evaporator and the accumulator already being openly connected with each otherl Although not shown in the figures there are many other physical embodiments of the teachings of this invention. For example, it is not necessaryfor the suction line or pipe 8 to extend all the waythrough the accumulator shell 14. It is only necessary that there be a length of the suction line 8 within the shell 14 and that this length within the shell be located in the upper portion of the chamber formed by the shell 14 so that the perforations 17 may be located on the top of the line 8 away from the surging refrigerant below. The line 8 could be crimped closed within the shell allowing the capillary line to extend on through the crimped portion and out into the evaporator 6 as shown through a seal where the crimpings 18 are located on the drawings.

Because of their high thermo-conductivity and also because of their ductility and malleability aluminum alloys and copper both are good materials for refrigeration tubing and piping. Aluminum alloys are the less expensive and their pristine surface brightness is more durable than the brightness of new copper surfaces. Therefore, aluminum alloy is employed for most of the structure of the refrigeration apparatus described above. Copper is superior however for elements the dimensions of which must be precise. For example, copper is the better material for the capillary tube.

Where copper is joined to aluminum the joint is liable to be unsatisfactory because of leakage, and where the joint is exposed to aqueous fluid, or even slight humidity, electrolytic action may be set up and cause corrosion. It is to be noted that the structure disclosed herein has only one joint where electrolytic action may occur that is exposed to moisture. That joint is at the fitting 9 where provisions for guarding against deterioration can be made since the fitting 9 would be utilized adjacent the suction intake of the compressor which is outside of the cabinet of the freezer or refrigerator. Joints between copper and aluminum allows that are immersed in refrigerant are not subject to electrolytic action so the joints made on the interior of the closed refrigeration system are safe from deterioration. Such copper-aluminum fittings as the fitting 9 are commercially available,

In summary there is disclosed refrigeration apparatus utilizing liquid and gaseous refrigerant which comprises an accumulator shell which cooperates with a suction line to provide a novel and useful accumulating means. The accumulator shell has formed therein an exit opening to receive the suction line. A length of the suction line lies within the shell. At least a part of this length of suction line is located in the upper part of the accumulator shell. The interior of said suction line communicates with the interior of the shell only through a plurality of perforations, which may be round, square, slot like, etc. The perforations are advantageously formed in the top of the length of suction line that is located in the upper portion of the shell. The shell also has formed therein a port for receiving the refrigerant from an evaporator. The port is advantageously located in the upper portion of the shell and is removed from a position directly over the perforations in said suction line so that refrigerant would not drop directly into said perforations. As discussed hereinbefore the capillary expansion line may be led through the suction line and the accumulator and be allowed to discharge into the evaporator.

The foregoing description and the accompanying drawings describe and illustrate apreferred form ofthis in- 4 vention but it is to be understood that the invention encompasses such variations as are within the spirit and scope of the invention as disclosed.

I claim:

1. In refrigerating apparatus the combination of an accumulator; a suction pipe, a capillary tube, and an evaporator coil; said accumulator comprising an elongated shell, said shell being generally cylindrical and being positioned in said apparatus with its major axis substantially horizontal, said suction pipe entering said shell through a nipple projecting from one end of said shell near the top thereof, said suction pipe protruding from the other end of said shell through a second nipple projecting from the other end of said shell near the top thereof, a portion of said suction pipe that is within said shell lying close to the top of said shell, said portion of said suction pipe having a series of perforations along its top through which gaseous refrigerant can be drawn from within said shell to within said suction pipe, a portion of said capillary tube lying within said suction pipe and extending therewith through said shell and thence into the intake end of said evaporator coil, said suction pipe being crimped about said capillary tube at one or more places to form a nearly fluid-tight seal between the interior of said shell and the interior of said evaporator coil, and a tailpipe leading from said evaporator coil into a port in the top of said shell.

2. In refrigerating apparatus the combination of an accumulator, a suction pipe, a capillary tube and an evaporator coil; said accumulator comprising an elongated shell, said shell being generally cylindrical and being positioned in said apparatus with its major axis substantially horizontal, said suction pipe entering said shell through one end thereof and protruding from the other end of said shell, the portion of said suction pipe that is within said shell lying close to the top of said shell, said portion of said suction pipe having a series of perforations along its top through which gaseous refrigerant can be drawn from within said shell to within said suction pipe, a portion of said capillary tube lying within said suction pipe and extending therewith through said shell and thence into the intake end of said evaporator coil, said suction pipe being crimped about said capillary tube at one or more places to form a nearly fluid-tight seal between the interior of said shell and the interior of said evaporator coil, and a conduit leading from said evaporator coil into a port in the top of said shell.

3. In refrigerating apparatus the combination of an accumulator, a suction pipe, a capillary tube and an evaporator coil; said accumulator comprising an elongated shell, said shell being positioned in said apparatus with its major axis substantially horizontal, said suction pipe entering said shell through a nipple projecting from one end of said shell, said suction pipe protruding from the other end of said shell through a second nipple projecting from the other end of said shell, the portion of said suction pipe that is within said shell lying close to the top of said shell, said portion of said suction pipe having a series of perforations along its top through which gaseous refrigerant can be drawn from within said shell to within said suction pipe, a portion of said capillary tube lying within said suction pipe and extending therewith through said shell and thence into the intake end of said evaporator coil, a nearly fluid-tight seal along said capillary tube between the interior of said shell and the interior of said evaporator coil, and a conduit leading from said evaporator coil into a port in the top of said shell.

4. In refrigerating apparatus, in combination, an evaporator coil, an accumulator comprising an elongated shell, said shell being positioned in said apparatus with its major axis substantially horizontal, a suction pipe entering said shell through one end of said shell near the tar EQ QQQ, staid u ti Pi s rq mdina fr h other nd of said shell, the portion of said suction pipe that is within said shell lying close to the top of said shell and having a series of perforations along its top through which gaseous refrigerant can be drawn from within said shell to within said suction pipe, a portion of a capillary [tube lying within said suction pipe and extending therewith through said shell and thence into the intake end of said evaporatorcoil, a nearly fluid-tight seal along said capillary tube between the interior of said shell and the interior of said evaporator coil, and a conduit leading from said evaporator coil into a port in the top of said shell.

5. In refrigerating apparatus having a compressor, a condenser, an evaporator, a capillary tube leading from said condenser to said evaporator, a conduit leading from said compressor to said condenser and a suction pipe through which refrigerant after being vaporized in said evaporator is returned to said compressor; the combination in such apparatus of an accumulator comprising an elongated shell, said shell being generally cylindrical and being positioned in said apparatus with its major axis substantially horizontal, said suction pipe entering said shell through one end of said shell near the top thereof, said suction pipe protruding from the other end of said shell, the portion of said suction pipe that is within said shell lying close to the top of said shell, said portion of said suction pipe having a series of perforations along its top through which gaseous refrigerant can be drawn from within said shell to within said suction pipe, a portion of said capillary tube lying within said suction pipe and extending therewith through said shell and thence into the intake end of said evaporator coil, said suction pipe being crimped about said capillary tube at one or more places to form a nearly fluid-tight seal between the interior of said shell and the interior of said evaporator'coil, and a conduit leading from said evaporator coil into a port in the top of said shell.

6. In refrigerating apparatus having a compressor, a condenser, an evaporator, a restricted passage in the form of a capillary tube leading from said condenser to said evaporator, a conduit leading from said compressor to said condenser and a suction pass-age in the form of a suction pipe through which refrigerant after being vaporized in said evaporator is returned to said compressor; the combination in such apparatus of an accumulator comprising an elongated shell, said shell being positioned in said apparatus with its major axis substantially horizontal, said suction pipe entering said shell through a nipple projecting from one end of said shell near the top thereof, said suction pipe protruding from the other end of said shell through a second nipple projecting from the other end of said shell, the portion of said suction pipe that is within said shell lying close to the top of said shell, said portion of said suction pipe having a series of perforations along its top through which gaseous refrigerant can be drawnfrom within said shell to within said suction pipe, a portion of said capillary tube lying within said suction pipe and extending therewith through said shell and thence into the intake end of said evaporator coil, a nearly fluidtight seal between the interior of said shell and the interior of said evaporator coil, and a tailpipe, leading from said evaporator coil into a port in the top of said shell.

7. In refrigerating apparatus having a compressor, a condenser, an evaporator, a capillary tube leading from said condenser to said evaporator, a conduit leading from said compressor to said condenser and a suction pipe through which refrigerant after being vaporized ind said evaporator is returned to said compressor; the combination in such apparatus of an accumulator comprising an elongated shell, said shell being positioned in said apparatus with its major axis substantially horizontal, said suction pipe entering said shell through one end of said shell near the top thereof, said suction pipe protruding from the other end of said shell, the portion of said suction pipe that is within said shell lying close to the top of said shell, said portion of said suction pipe having a series of perforations along its top through which gase ous refrigerant can be drawn from within said shell to within said suction pipe, a portion of said capillary tube lying within said suction pipe and extending therewith through said shell and thence into the intake end of said evaporator coil, a nearly fluid-tight seal along said capillary tube between the interior of said shell and the interior of said evaporator coil, and a conduit leading from said evaporator coil into a port in the top of said shell.

8. In refrigerating apparatus having a compressor, a condenser, an evaporator, a restricted passage in the form of a capillary tube leading from said condenser to said evaporator, a conduit leading from said compressor to said condenser and a suction passage in the form of a suction pipe through which refrigerant after being vaporized in said evaporator is returned to said compressor; the combination in such apparatus of an accumulator comprising an elongated shell, said shell being generally cylindrical and being positioned in said apparatus with its major axis substantially horizontal, said suction pipe entering said shell through a nipple projecting from one end of said shell near the top thereof, said suction pipe protruding from the other end of said shell through a second nipple projecting from the other end of said shell, the portion of said suction pipe that is within said shell lying close to the top of said shell, said portion of said suction pipe having a series of perforations along its top through which gaseous refrigerant can be drawn from within said shell to within said suction pipe, a portion of said capillary tube lying within said suction pipe and extending therewith through said shell and thence into the intake end of said evaporator coil, said suction pipe being crimped about said capillary tube at one or more places to form a nearly fluid-tight seal between the interior of said shell and the interior of said evaporator coil, and a conduit leading from said evaporator coil into a port in the top of said shell.

9. In refrigerating apparatus, in combination; an accumulator, an evaporator coil having an inlet and an outlet, a suction line, a capillary tube, and sealing means; said accumulator being connected to said suction line; said evaporator coil having both its inlet and outlet connected to said accumulator; a portion of said capillary tube lying within said suction line and extending through said suction line and said accumulator into said inlet of said evaporator; said sealing means sealing said inlet of said evaporator around said capillary tube.

10. In refrigerating apparatus, in combination; an accumulator, an evaporator coil having an inlet and an outlet, a suction line, and a capillary tube; said accumulator being connected to said suction line; said evaporator coil having both its inlet and outlet connected to said accumulator; a portion of said capillary tube lying within said suction line and extending through said suction line and said accumulator into said inlet of said evaporator; said evaporator having its inlet sealed around said capillary tube.

11. In refrigeration apparatus utilizing liquid and gaseous refrigerant, an accumulator comprising a shell; a suction line; an evaporator coil having its inlet and outlet connected to said accumulator; a capillary tube; said shell having an exit opening formed therein for receiving said suction line; a length of said suction line being within said shell; a part of said length being located in the upper portion of said shell; the interior of said suction line communicating with the interior of said shell only through a plurality of perforations formed in the top of said length of suction line located in the upper portion of said shell; a portion of said capillary tube lying within said suction line and extending through said suction line in said accumulator to said inlet of said evaporator; said evaporator inlet being sealed around said capillary tube.

12. In refrigeration apparatus utilizing liquid and gaseous refrigerant, an accumulator comprising a shell; a suction line; an evaporator coil having an inlet and an outlet;

a capillary tube; said shell having an exit opening formed therein for receiving said suction line; a length of said suction line being within said shell; a part of said length being located in the upper portion of said shell; the interior of said suction line communicating with the interior of said shell only through a plurality of perforations formed in the top of said length of suction line located in the upper portion of said shell; the outlet and inlet of said evaporator coil being connected to said accumulator; said outlet from said evaporator being connected to the upper portion of said shell at a position removed from said perforations in said suction line to prevent liquid refrigerant from falling into said perforations; a portion of said capillary tube lying within said suction line and extending through said suction line and said accumulator into said inlet of said evaporator; said inlet of said evaporator being sealed around said capillary tube.

13. In refrigeration apparatus utilizing liquid and gaseous refrigerants, an accumulator comprising an elongated shell positioned with its major axis substantially horizontal; a suction line; an evaporator having an inlet and an outlet; a capillary tube; a length of said suction line being within said shell being substantially horizontal and located in the upper portion of the chamber formed by said shell; said evaporator coil having its inlet and outlet connected to said accumulator shell; a portion of said capillary tube lying within said suction line and extending through said suction line and said accumulator into said inlet of said evaporator; the interior of said suction line communicating with the interior of said shell only through a plurality of perforations formed in said horizontal length of said suction line within said shell; said evaporator inlet being sealed around said capillary tube.

References Cited in the file of this patent UNITED STATES PATENTS 2,192,368 Ray Mar. 5, 1940 2,224,377 Clark Dec 10, 1940 2,393,854 Carpenter Jan. 29, 1946 2,760,346 Grenell et a1. Aug. 28, 1956 2,787,135 Smith Apr. 2, 1957 2,819,592 Smith Jan. 14, 1958 

